Assessing the Electrocatalytic Properties of the (Cp*RhIII)2+-Polyoxometalate Derivative [H2PW11O39(RhIIICp*(OH2))]3- towards CO2 Reduction

Article abstract of DOI:10.1002/ejic.201800454

Storage of electricity produced intermittently by renewable energy sources is a societal issue. Besides the use of batteries and supercapacitors, conversion of excess electricity into chemical energy is also actively investigated. The conversion of CO₂ to fuel or fuel precursors is an option that requires the use of a catalyst to overcome the high activation energy barrier. Of molecular catalysts, metal complexes with polypyridyl ligands are well represented, among which the [Cp*Rh(bpy)Cl]⁺ and [M(bpy)(CO)₃X] (M = Re, Mn) complexes. As redox non-innocent ligand, the bipyridine ligand is generally involved in the reduction mechanisms. It is thus tempting to replace it by other redox non-innocent ligands such as vacant polyoxometalates (POMs). We have thus prepared [α-H₂PW₁₁O₃₉(Rh^IIICp*(OH₂))]^3- which is closely related to [Cp*Rh^III(bpy)Cl]⁺ by substitution of the monovacant [PW₁₁O₃₉]^7- Keggin-type POM for the bipyridine ligand. Its activity towards CO₂ reduction has been assessed in acetonitrile in the presence of water. Compared to [Cp*Rh(bpy)Cl]⁺ that produces formate selectively over CO and H₂, the POM derived catalyst favors proton reduction over CO₂ reduction.

Full text of DOI:10.1002/ejic.201800454

A Journal of
Accepted Article
Title: Assessing the electrocatalytic properties of the {Cp*Rh(III)}2+
Polyoxometalate derivative [H2PW11O39{Rh(III)Cp*(OH2)}]3-
towards CO2 reduction
Authors: Marcelo Girardi, Dominique Platzer, Sophie Griveau,
Fethi Bedioui, Sandra Alves, Anna Proust, and Sébastien
Blanchard
This manuscript has been accepted after peer review and appears as an
Accepted Article online prior to editing, proofing, and formal publication
of the final Version of Record (VoR). This work is currently citable by
using the Digital Object Identifier (DOI) given below. The VoR will be
published online in Early View as soon as possible and may be different
to this Accepted Article as a result of editing. Readers should obtain
the VoR from the journal website shown below when it is published
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content of this Accepted Article.
To be cited as: Eur. J. Inorg. Chem. 10.1002/ejic.201800454
Link to VoR: http://dx.doi.org/10.1002/ejic.201800454

European Journal of Inorganic Chemistry
10.1002/ejic.201800454
Assessing the electrocatalytic properties of the
2
+
{
Cp*Rh(III)} -Polyoxometalate derivative
3
-
[
H PW O {Rh(III)Cp*(OH )}] towards CO reduction
2
11 39
2
2
ꢀ
[
a,b]
[a]
[b]
[b]
[a]
Marcelo Girardi,
Dominique Platzer, Sophie Griveau, Fethi Bedioui, Sandra Alves,
[
a]
[a]
Anna Proust,* Sébastien Blanchard*
[
a] Sorbonne Université, CNRS, Institut Parisien de Chimie Moléculaire, IPCM, 4 Place
Jussieu, F-75005 Paris, France, anna.proust@sorbonne-universite.fr,
sebastien.blanchard@sorbonne-universite.fr http://www.ipcm.fr
[
b] Chimie ParisTech - PSL Research University, INSERM 1022, CNRS 8258, Université́
Paris Descartes, Unité de Technologies Chimiques et Biologiques pour la Santé, (UTCBS),
5005 Paris, France
7
Abstract:ꢀStorage of electricity produced intermittently by renewable energy sources is a societal issue. Besides
the use of batteries and supercapacitors, conversion of excess electricity into chemical energy is also actively
investigated. The conversion of CO
2
to fuel or fuel precursors is an option that requires the use of a catalyst to
overcome the high activation energy barrier. Of molecular catalysts, metal complexes with polypyridyl ligands are
+
3
well represented, among which the [Cp*Rh(bpy)Cl] and [M(bpy)(CO) X] ( M = Re, Mn) complexes. As redox non-
innocent ligand, the bipyridine ligand is generally involved in the reduction mechanisms. It is thus tempting to
replace it by other redox non-innocent ligands such as vacant polyoxometalates (POMs). We have thus prepared
3
-
+
[
[
α-H
2
PW11
O
39{Rh(III)Cp*(OH
2
}] which is closely related to [Cp*Rh(III)(bpy)Cl] by substitution of the monovacant
7-
PW11
O
39
]
Keggin-type POM for the bipyridine ligand. Its activity towards CO reduction has been assessed in
2
+
acetonitrile in the presence of water. Compared to [Cp*Rh(bpy)Cl] that produces formate selectively over CO and
H
2 2
, the POM derived catalyst favours proton reduction over CO reduction.ꢀꢀꢀꢀ
ꢀ
ꢀ
Introductionꢀꢀꢀ
Whileꢀfossilꢀenergyꢀstillꢀremainsꢀpredominant,ꢀitsꢀimpactꢀonꢀtheꢀenvironment,ꢀespeciallyꢀdueꢀtoꢀtheꢀ
emissionꢀofꢀtheꢀgreenhouseꢀgasꢀCO ,ꢀhasꢀledꢀtoꢀtheꢀdevelopmentꢀofꢀalternativeꢀapproachesꢀ(solar,ꢀ
wind,..)ꢀandꢀtheirꢀincreaseꢀinꢀtheꢀenergyꢀmix. ꢀHowever,ꢀaꢀmainꢀdrawbackꢀofꢀtheseꢀenergyꢀsourcesꢀisꢀ
2
[
1]
[
2]
theirꢀintermittence,ꢀandꢀaꢀsignificantꢀchallengeꢀisꢀtheꢀstorageꢀofꢀtheꢀsoꢀproducedꢀelectricity. ꢀWhileꢀ
[
3]
electrochemicalꢀstorageꢀintoꢀbatteriesꢀisꢀanꢀoption, ꢀstorageꢀwithinꢀchemicalꢀbonds,ꢀofferingꢀmuchꢀ
higherꢀ gravimetricꢀ densities,ꢀ isꢀ appealing,ꢀ notablyꢀ forꢀ transportationꢀ purposes.ꢀ Besidesꢀ aꢀ possibleꢀ
[
4]
2
hydrogenꢀ economy, ꢀ thereꢀ hasꢀ beenꢀ aꢀ renewedꢀ interestꢀ towardsꢀ CO ꢀ reductionꢀ overꢀ theꢀ lastꢀ
[
5,6]
years. ꢀꢀ
ꢀ
ꢀ
ꢀ
Theꢀ reductionꢀ ofꢀ CO2ꢀ isꢀ aꢀ multiproton/multielectronꢀ processꢀ thatꢀ canꢀ leadꢀ toꢀ aꢀ varietyꢀ ofꢀ
1
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European Journal of Inorganic Chemistry
10.1002/ejic.201800454
[
7]
products,ꢀwithꢀdihydrogenꢀbeingꢀtheꢀmainꢀsideꢀproduct. ꢀMolecularꢀcatalystsꢀthatꢀproduceꢀCOꢀareꢀbyꢀ
[
6,8]
farꢀtheꢀmostꢀabundant. ꢀCarefulꢀanalysisꢀofꢀtheꢀreactionꢀpathwaysꢀhasꢀledꢀtoꢀmolecularꢀtuningꢀofꢀ
theseꢀcatalystsꢀforꢀimprovedꢀperformances.ꢀForꢀexample,ꢀincreasingꢀtheꢀstericꢀhindranceꢀaroundꢀtheꢀ
[
9,10]
catalystꢀenhancedꢀtheꢀcatalyticꢀrateꢀbyꢀtwoꢀordersꢀofꢀmagnitudeꢀinꢀtheꢀ[Mn(bpy)(CO)
3
Br]ꢀfamily,
ꢀꢀ
ꢀ
[
11]
whileꢀ dimericꢀ Pd-triphosphineꢀ complexesꢀ allowedꢀ forꢀ cooperativityꢀ betweenꢀ theꢀ metalꢀ centers.
[
12,13]
[14]
Tuningꢀ theꢀ secondꢀ sphereꢀ interactionsꢀ (protonsꢀ relays,
ꢀ electrostaticꢀ stabilization, ...)ꢀ inꢀ ironꢀ
porphyrinꢀcomplexesꢀhasꢀrecentlyꢀledꢀtoꢀaꢀwaterꢀsolubleꢀcatalystꢀwithꢀhighꢀturnoverꢀfrequencyꢀ(TOF)ꢀ
[
15]
[16]
andꢀlowꢀoverpotential, ꢀallowingꢀtheꢀcouplingꢀofꢀaꢀmodelꢀelectrolyzerꢀtoꢀaꢀphotovoltaicꢀpanel.
However,ꢀtheꢀuseꢀofꢀCOꢀasꢀaꢀfuelꢀsourceꢀrequiresꢀfurtherꢀtransformation,ꢀandꢀusuallyꢀitsꢀcombinationꢀ
withꢀH ꢀtoꢀgenerateꢀhydrocarbonsꢀviaꢀtheꢀFisher-Tropschꢀprocessꢀisꢀproposed.ꢀReductionꢀofꢀCO ꢀtoꢀ
ꢀ
2
2
[
17]
formicꢀacid/formateꢀrepresentsꢀanꢀappealingꢀalternative. ꢀFormicꢀacidꢀisꢀaꢀliquidꢀthatꢀcanꢀbeꢀeitherꢀ
thoughtꢀofꢀasꢀaꢀsourceꢀofꢀprotonsꢀandꢀelectronsꢀforꢀaꢀfuelꢀcellꢀorꢀasꢀaꢀhighꢀdensityꢀhydrogenꢀstorageꢀ
[
18]
unit, ꢀbutꢀisꢀalsoꢀaꢀcommodityꢀchemical.ꢀꢀWhileꢀearlyꢀonꢀtheꢀselectivityꢀofꢀsomeꢀmolecularꢀcatalystsꢀ
[
19–21]
hasꢀbeenꢀreportedꢀtoꢀbeꢀpartiallyꢀshiftedꢀfromꢀCOꢀtoꢀHCOOH,
ꢀrecentꢀreportsꢀofꢀcatalystꢀtrulyꢀ
[
22,23]
selectiveꢀforꢀformateꢀhaveꢀappearedꢀinꢀtheꢀliterature.
ꢀMolecularꢀcatalystsꢀthatꢀgoꢀbeyondꢀtheꢀ
[
24,25]
twoꢀelectronꢀreductionꢀofꢀCO
2
ꢀareꢀevenꢀscarcer.
ꢀꢀ
ꢀ
Polyoxometalatesꢀ(POMs)ꢀareꢀoxoclustersꢀofꢀearlyꢀtransitionꢀmetalsꢀinꢀhighꢀoxidationꢀstatesꢀ
VI
VI
(
typicallyꢀW ,Mo ,...)ꢀoftenꢀthoughtꢀofꢀasꢀmolecularꢀoxides.ꢀTheyꢀdisplayꢀaꢀgreatꢀdiversityꢀinꢀshape,ꢀ
[
26]
size,ꢀchargeꢀandꢀpropertiesꢀandꢀhaveꢀthusꢀfoundꢀnumerousꢀapplications,ꢀfromꢀcatalysis ꢀꢀtoꢀmaterialꢀ
[
27–30]
[31–33]
science
ꢀorꢀbiochemicalꢀapplications.
ꢀMostꢀrelevantꢀhere,ꢀsomeꢀPOMsꢀdisplayꢀremarkableꢀ
redoxꢀproperties,ꢀandꢀhaveꢀinꢀparticularꢀbeenꢀshownꢀtoꢀpromoteꢀtheꢀelectrocatalyticꢀreductionꢀofꢀ
[
34,35]
protons,
ꢀandꢀevenꢀtheꢀmultielectron/multiprotonꢀreductionꢀofꢀnitrite,ꢀorꢀmoreꢀseldomꢀnitrate,ꢀtoꢀ
[
36–40]
ammonia.
ꢀ Surprisingly,ꢀ onlyꢀ aꢀ fewꢀ reportsꢀ ofꢀ CO
2
ꢀ reductionꢀ withꢀ POMsꢀ exists:ꢀ whileꢀ inꢀ 1990ꢀ
7
- [41]
YamaseꢀproposedꢀtheꢀphotoreductionꢀinꢀwaterꢀofꢀCO
2
ꢀtoꢀCH
4
ꢀcatalyzedꢀbyꢀ[PTi
2
W
10
O
40] , ꢀNeumannꢀ
5
-
[42]
publishedꢀmoreꢀrecentlyꢀthatꢀ[RuSiW11
O
39] ꢀpromotesꢀtheꢀphotoreductionꢀofꢀCO
2
ꢀtoꢀCOꢀinꢀtoluene.
ꢀ
[
43,44]
6-ꢀ
Followingꢀ Kozik'sꢀ work,
ꢀ weꢀ haveꢀ reportedꢀ thatꢀ [CoSiW11
O
39
]
isꢀ anꢀ electrocatalystꢀ inꢀ
dichloromethaneꢀforꢀtheꢀtwoꢀelectronꢀreductionꢀofꢀcarbonꢀdioxideꢀtoꢀCO,ꢀbutꢀalso,ꢀinꢀtheꢀpresenceꢀofꢀ
[
45]
acid,ꢀtoꢀaꢀveryꢀseldomꢀobservedꢀfourꢀelectronꢀreductionꢀproduct,ꢀformaldehyde. ꢀBesidesꢀbeingꢀtheꢀ
[
46]
catalyticꢀspecies, ꢀꢀanotherꢀroleꢀforꢀtheꢀPOMꢀasꢀanꢀelectron/protonꢀrelayꢀhasꢀalsoꢀbeenꢀrecentlyꢀ
[
47–49]
proposed.
ꢀꢀ
ꢀ
Besidesꢀtheꢀnecessityꢀtoꢀworkꢀinꢀaꢀnon-coordinatingꢀapolarꢀsolventꢀsuchꢀasꢀdichloromethane,ꢀ
6
-
[45]
2
anotherꢀdrawbackꢀofꢀ[CoSiW11O39] ꢀasꢀanꢀelectrocatalystꢀforꢀCO ꢀreductionꢀisꢀitsꢀlowꢀactivity. ꢀToꢀ
moveꢀ forward,ꢀ weꢀ aimedꢀ atꢀ investigatingꢀ theꢀ associationꢀ ofꢀ theꢀ POMꢀ propertiesꢀ withꢀ thoseꢀ ofꢀ aꢀ
knownꢀ catalyst,ꢀ preferablyꢀ inꢀ moreꢀ “classical”ꢀ solventsꢀ likeꢀ acetonitrileꢀ orꢀ evenꢀ water.ꢀ Numerousꢀ
ꢀ
2
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European Journal of Inorganic Chemistry
10.1002/ejic.201800454
[
50–56]
examplesꢀofꢀorganometallicꢀderivativesꢀofꢀPOMsꢀwereꢀdescribedꢀinꢀtheꢀliterature.
ꢀForꢀexample,ꢀ
someꢀ ofꢀ usꢀ haveꢀ discussedꢀ theꢀ reactionꢀ betweenꢀ [Ru(arene)Cl
2
]
2
ꢀ andꢀ theꢀ monovacantꢀ POMꢀ
7
-ꢀ
5-
8-
}] ꢀ
[
PW11
O
39
]
andꢀ describedꢀ theꢀ [PW11
O
39{Ru(arene)(H
2
O)}] ꢀ andꢀ [{PW11
O
39{Ru(arene)}}
2
{WO
2
[
57]
derivatives. ꢀ Interestingly,ꢀ inꢀ theseꢀ complexes,ꢀ theꢀ monovacantꢀ POMꢀ actsꢀ onlyꢀ asꢀ aꢀ bidentateꢀ
ligand,ꢀleavingꢀanꢀexchangeableꢀcoordinationꢀsiteꢀonꢀtheꢀRuꢀcenter.ꢀReasoningꢀthatꢀtheꢀ[Cp*RhCl(µ-
Cl)]
2
ꢀ precursorꢀ shouldꢀ haveꢀ aꢀ quiteꢀ similarꢀ reactivity,ꢀ weꢀ haveꢀ thusꢀ investigatedꢀ theꢀ graftingꢀ ofꢀ aꢀ
2
+
7-ꢀ
{
Cp*Rh(III)} ꢀfragmentꢀonꢀtheꢀmonovacantꢀ[PW11
O
39] ꢀanion,ꢀinꢀorderꢀtoꢀcompareꢀtheꢀreactivityꢀꢀofꢀ
+
theꢀ soꢀ formedꢀ organometallicꢀ derivativeꢀ withꢀ thatꢀ ofꢀ [Cp*Rh(III)(bpy)Cl] ,ꢀ aꢀ knownꢀ CO
2
ꢀ reductionꢀ
[
19,58,59]
catalystꢀthatꢀproducesꢀformateꢀselectivelyꢀoverꢀCOꢀandꢀH
2
.
ꢀIndeed,ꢀthisꢀstudyꢀwillꢀalsoꢀallowꢀtheꢀ
comparisonꢀbetweenꢀtheꢀPOMꢀandꢀbipyridineꢀasꢀredoxꢀnon-innocentꢀligands.ꢀ
ꢀ
Resultsꢀandꢀdiscussionꢀ
*
Synthesisꢀandꢀcharacterizationꢀofꢀ(TBA)
3
[α-H
2
PW11
O
39{Rh(III)Cp (OH
2
)}]ꢀꢀ
Cl
Rh
i) AgNO3
Cl
Cl
Rh
Rh OH2
Cl
ii)
3
-
[
α-H PW O {RhCp*(OH )}]
2 11 39 2
5
-
[
α-H PW O ]
2
11 39
ꢀ
3
-
Schemeꢀ1.ꢀSynthesisꢀofꢀtheꢀorganometallicꢀderivativeꢀ[α-H
2
PW11 39{Rh(III)Cp*(OH }] .ꢀ(theꢀPOMꢀskeletonꢀisꢀdisplayedꢀinꢀ
O
2
polyhedralꢀrepresentation)ꢀ
ꢀ
ꢀ
Additionꢀ underꢀ inertꢀ atmosphereꢀ ofꢀ aꢀ freshlyꢀ preparedꢀ yellowꢀ solutionꢀ ofꢀ
Cp*Rh(CH CN) ](BF ꢀinꢀdichloromethaneꢀtoꢀaꢀsolutionꢀofꢀ(TBA) [α-H 39]ꢀinꢀdichloromethaneꢀ
[
3
3
4
)
2
5
2
PW11O
inꢀ theꢀ presenceꢀ ofꢀ triethylamineꢀ yieldsꢀ anꢀ orangeꢀ solutionꢀ (TBAꢀ standsꢀ forꢀ theꢀ tetra-n-
3
1
butylammoniumꢀcationꢀandꢀCp*ꢀforꢀtheꢀpentamethyl-cyclopentadienylꢀanion).ꢀAfterꢀoneꢀnight,ꢀitsꢀ Pꢀ
NMRꢀspectrumꢀshowsꢀaꢀsingleꢀnewꢀpeakꢀatꢀδ=-12.24ꢀppm,ꢀwithꢀcompleteꢀconsumptionꢀofꢀtheꢀstartingꢀ
3 2 2 2
vacantꢀPOMꢀatꢀδ=-11.50ꢀppmꢀ(FigureꢀS1).ꢀꢀUponꢀtreatment,ꢀ(TBA) [α-H PW11O39{Rh(III)Cp*(OH }].H Oꢀ
isꢀrecoveredꢀasꢀanꢀorangeꢀpowder,ꢀasꢀconfirmedꢀbyꢀitsꢀelementalꢀanalysisꢀandꢀmassꢀspectrometryꢀ(ꢀ
FigureꢀS4).ꢀTheꢀnumberꢀofꢀwaterꢀmoleculesꢀwasꢀdeterminedꢀbyꢀthermogravimetricꢀanalysisꢀ(Figureꢀ
S5),ꢀwhileꢀtheꢀratioꢀofꢀTBA/Cp*ꢀisꢀconfirmedꢀbyꢀtheꢀrelativeꢀintegrationꢀofꢀtheꢀmethylꢀprotonsꢀofꢀtheꢀ
ꢀ
3
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European Journal of Inorganic Chemistry
10.1002/ejic.201800454
-
+
1
Cp* ꢀ ligandꢀ comparedꢀ toꢀ thoseꢀ ofꢀ theꢀ TBA ꢀ cationꢀ onꢀ theꢀ Hꢀ NMRꢀ spectrumꢀ (Figureꢀ S2).ꢀ ꢀ Theꢀ IRꢀ
spectrumꢀ ofꢀ (TBA)
3 2 2 2
[α-H PW11O39{Rh(III)Cp*(OH }].H Oꢀ displaysꢀ theꢀ characteristicꢀ signatureꢀ ofꢀ theꢀ
-
1
Kegginꢀstructure.ꢀMostꢀnotably,ꢀtheꢀν(P-O)ꢀbandꢀisꢀstillꢀsplitꢀintoꢀtwoꢀcomponentsꢀ(∆σ=59ꢀcm ),ꢀwhichꢀ
7
-
-1
isꢀquiteꢀsimilarꢀtoꢀthatꢀofꢀtheꢀstartingꢀ[PW11
O39] ꢀanionꢀ(∆σ=52ꢀcm )ꢀ(seeꢀFigureꢀ1).ꢀThisꢀsplittingꢀisꢀ
[
60]
diagnosticꢀofꢀaꢀcationꢀpartiallyꢀincorporatedꢀintoꢀtheꢀlacunaꢀofꢀtheꢀPOM. ꢀWeꢀthusꢀproposeꢀthatꢀtheꢀ
2
+
vacantꢀPOMꢀactsꢀasꢀaꢀbidentateꢀligandꢀonꢀtheꢀ{Cp*Rh(III)} ꢀmoiety,ꢀleavingꢀanꢀaccessibleꢀcoordinationꢀ
2
+
[57]
siteꢀonꢀtheꢀmetalꢀion,ꢀasꢀwasꢀpreviouslyꢀobservedꢀforꢀtheꢀ{Ru-arene} ꢀderivatives. ꢀIndeed,ꢀadditionꢀ
3
ofꢀTBANO
3
ꢀinꢀanꢀNMRꢀtubeꢀcontainingꢀaꢀsolutionꢀofꢀ(TBA)
3
[H
2
PW11
O
39{Rh(III)Cp*(OH
2
)}]ꢀinꢀd -MeCNꢀ
leadsꢀtoꢀaꢀvariationꢀofꢀꢀtheꢀchemicalꢀshiftꢀofꢀtheꢀmethylꢀofꢀtheꢀCp*ꢀligandꢀ(fromꢀ1.77ppmꢀꢀtoꢀ1.82ꢀ
-
ꢀ
III
ppm),ꢀlikelyꢀresultingꢀfromꢀtheꢀexchangeꢀofꢀaꢀwaterꢀmoleculeꢀforꢀNO
3
onꢀtheꢀRh ꢀcenterꢀ(seeꢀFigureꢀ
2
).ꢀꢀꢀ
ꢀ
(I)
(II)
(III)
ꢀ
ꢀ
ꢀ
Figureꢀ1.ꢀPartꢀofꢀtheꢀFT-IRꢀspectraꢀofꢀ(TBA)
3
[H
(
2
PW11
O
39{Rh(III)Cp*(OH
)
2 2
2
)}]ꢀ(black),ꢀmonovacantꢀPOMꢀprecursorꢀ(blue)ꢀandꢀ
RhCp*Cl ꢀprecursorꢀ(green)ꢀ
ꢀ
4
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European Journal of Inorganic Chemistry
10.1002/ejic.201800454
ꢀ
1
3
Figureꢀ2.ꢀPartꢀofꢀtheꢀ HꢀNMRꢀspectrumꢀofꢀ(TBA)
3
[H
2
PW11
O
2
39{Rh(III)Cp*(OH )}]ꢀinꢀd -MeCNꢀ(top)ꢀandꢀitsꢀevolutionꢀuponꢀ
3
TBANO ꢀadditionꢀ(bottom).ꢀ
ꢀ
Electrochemicalꢀexperimentsꢀꢀ
3 2 2
Theꢀ redoxꢀ propertiesꢀ ofꢀ (TBA) [α-H PW11O39{Rh(III)Cp*(OH )}]ꢀ haveꢀ beenꢀ assessedꢀ byꢀ cyclicꢀ
voltammetryꢀinꢀacetonitrile,ꢀusingꢀTBABF4ꢀasꢀaꢀsupportingꢀelectrolyte.ꢀAllꢀpotentialsꢀareꢀgivenꢀversusꢀaꢀ
calomelꢀelectrodeꢀinꢀ1MꢀLiClꢀsolutionꢀ(0.28V/ꢀNHE)ꢀasꢀaꢀreference.ꢀꢀ
ꢀ
3 2 2
Theꢀelectrochemicalꢀbehaviorꢀofꢀ(TBA) [α-H PW11O39{Rh(III)Cp*(OH )}]ꢀunderꢀargonꢀisꢀratherꢀ
complex,ꢀasꢀdisplayedꢀonꢀFigureꢀ3ꢀ(curveꢀI).ꢀSeveralꢀreductionꢀprocessesꢀareꢀobservedꢀbetweenꢀ-0.5Vꢀ
andꢀ -2V,ꢀ someꢀ ofꢀ themꢀ beingꢀ irreversible.ꢀ Thisꢀ isꢀ howeverꢀ notꢀ surprising,ꢀ asꢀ weꢀ canꢀ expectꢀ theꢀ
2
+
superpositionꢀ ofꢀ bothꢀ POM-basedꢀ andꢀ {Cp*Rh(III)} ꢀ reductionꢀ processes.ꢀ Indeed,ꢀ electrochemicalꢀ
5
-
II
II
studiesꢀofꢀtransitionꢀmetalꢀsubstitutedꢀPOMsꢀ[MPW11
O39] ꢀ(M=Ni ,ꢀCo )ꢀinꢀacetonitrileꢀhaveꢀshownꢀaꢀ
[
61]
firstꢀ W-basedꢀ reductionꢀ processꢀ aroundꢀ -1.15Vꢀ andꢀ aꢀ secondꢀ aroundꢀ -1.8V, ꢀ whileꢀ thoseꢀ ofꢀ
+
ꢀ
[19]
[
Cp*Rh(III)(bpy)Cl] ꢀ ledꢀ toꢀ pseudo-reversibleꢀ redoxꢀ processesꢀ atꢀ -0.82Vꢀ andꢀ -2.23Vꢀ (Figureꢀ S7).
ꢀ
5
-
+
Moreover,ꢀtheꢀcyclicꢀvoltammogramsꢀofꢀbothꢀ[MPW11O39] ꢀandꢀ[Cp*Rh(III)(bpy)Cl] ꢀareꢀmodifiedꢀinꢀ
theꢀ presenceꢀ ofꢀ addedꢀ protons,ꢀ theꢀ latterꢀ withꢀ irreversibleꢀ processesꢀ dueꢀ toꢀ theꢀ formationꢀ ofꢀ aꢀ
[
19]ꢀ
3-
2 2
Cp*Rh-hydrideꢀ intermediate. Asꢀ theꢀ [H PW11O39{Rh(III)Cp*(OH )}] ꢀ speciesꢀ isꢀ itselfꢀ aꢀ potentialꢀ
sourceꢀofꢀprotons,ꢀitꢀdoesꢀfurtherꢀcomplicateꢀtheꢀredoxꢀsignature.ꢀThus,ꢀtheꢀcompleteꢀattributionꢀofꢀ
theꢀelectrochemicalꢀresponseꢀappearsꢀquiteꢀchallengingꢀandꢀisꢀbeyondꢀtheꢀscopeꢀofꢀthisꢀstudy.ꢀMoreꢀ
2
relevantꢀhereꢀisꢀtheꢀevolutionꢀofꢀtheꢀelectrochemicalꢀsignatureꢀinꢀtheꢀpresenceꢀofꢀwater,ꢀCO ꢀorꢀboth.ꢀ
ꢀ
5
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European Journal of Inorganic Chemistry
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ꢀ
-
1
Figureꢀ3.ꢀꢀComparisonꢀofꢀcyclicꢀvoltammogramsꢀatꢀaꢀglassyꢀcarbonꢀelectrodeꢀatꢀaꢀscanꢀrateꢀofꢀ100ꢀmV.s ꢀinꢀacetonitrileꢀ+ꢀ0.1ꢀ
4 3 2 2
MꢀTBABF ꢀunderꢀargonꢀofꢀaꢀ1ꢀmMꢀsolutionꢀofꢀ(TBA) [H PW11O39{Rh(III)Cp*(H O)}]ꢀ(curveꢀI),ꢀafterꢀadditionꢀofꢀ1%ꢀvolumeꢀofꢀ
waterꢀ(curveꢀII),ꢀ5%ꢀvolumeꢀofꢀwaterꢀ(curveꢀIII)ꢀandꢀ10%ꢀvolumeꢀofꢀwaterꢀ(curveꢀIV);ꢀE(VꢀvsꢀHg Cl /Hg,ꢀ1MꢀLiCl).ꢀꢀ
2 2
ꢀ
ꢀ
3
Uponꢀadditionꢀofꢀ0ꢀtoꢀ10ꢀ%ꢀofꢀwaterꢀ(v/vꢀCH CN)ꢀunderꢀargon,ꢀthereꢀisꢀanꢀoverallꢀshiftꢀofꢀtheꢀ
wave'sꢀpotentialsꢀtowardꢀlessꢀnegativeꢀvalues,ꢀtogetherꢀwithꢀanꢀincreaseꢀofꢀintensityꢀ(Figureꢀ3ꢀcurvesꢀ
II-IV).ꢀ Inꢀ particular,ꢀ thereꢀ isꢀ aꢀ largeꢀ increaseꢀ ofꢀ theꢀ intensityꢀ ofꢀ theꢀ mostꢀ negativeꢀ wavesꢀ (belowꢀ -
1
.25V),ꢀ whichꢀ couldꢀ eitherꢀ originatesꢀ fromꢀ aꢀ facilitationꢀ ofꢀ theꢀ POMꢀ skeletonꢀ reductionꢀ uponꢀ
ꢀ
6
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European Journal of Inorganic Chemistry
10.1002/ejic.201800454
protonation,ꢀ orꢀ fromꢀ catalyticꢀ protonꢀ reduction.ꢀ Controlledꢀ potentialꢀ electrolysisꢀ ofꢀ aꢀ 0.5ꢀ mMꢀ
solutionꢀofꢀ(TBA) [H 39{Rh(III)Cp*(OH )}]ꢀinꢀacetonitrileꢀperformedꢀatꢀ-1.8Vꢀinꢀtheꢀpresenceꢀofꢀ
%ꢀofꢀwaterꢀledꢀtoꢀtheꢀdetection,ꢀafterꢀ90ꢀminutesꢀofꢀelectrolysis,ꢀofꢀanꢀamountꢀofꢀH ꢀcorrespondingꢀ
),ꢀ howeverꢀ withꢀ aꢀ lowꢀ faradicꢀ yieldꢀ (10ꢀ %).ꢀ Duringꢀ theꢀ courseꢀ ofꢀ
electrolysis,ꢀ theꢀ solutionꢀ progressivelyꢀ turnedꢀ blue:ꢀ thisꢀ colorꢀ isꢀ characteristicꢀ ofꢀ partiallyꢀ reducedꢀ
3
2
PW11
O
2
5
2
-
6ꢀ
toꢀ 0.33ꢀ TONꢀ (3.3ꢀ 10 molꢀ ofꢀ H
2
V
VI [62]
POMs,ꢀoriginatingꢀfromꢀintervalenceꢀchargeꢀtransferꢀbandsꢀbetweenꢀW ꢀandꢀW , ꢀthusꢀconfirmingꢀ
thatꢀpartꢀofꢀtheꢀelectronsꢀareꢀindeedꢀusedꢀtoꢀreduceꢀtheꢀPOMs.ꢀ
ꢀ
-
1
Figureꢀ4.ꢀComparisonꢀofꢀcyclicꢀvoltammogramsꢀatꢀaꢀglassyꢀcarbonꢀelectrodeꢀatꢀaꢀscanꢀrateꢀofꢀ100ꢀmV.s ꢀinꢀacetonitrileꢀ+ꢀ0.1ꢀ
MꢀTBABF ꢀofꢀaꢀ1ꢀmMꢀsolutionꢀofꢀ(TBA) [H 39{Rh(III)Cp*(H O)}]ꢀunderꢀargonꢀ(curveꢀI)ꢀandꢀCO ꢀ(curveꢀII),ꢀafterꢀadditionꢀ
4
3
2
PW11
O
2
2
2 2
ofꢀ1%ꢀvolumeꢀofꢀwaterꢀ(curveꢀIII)ꢀandꢀ5%ꢀvolumeꢀofꢀwaterꢀ(curveꢀIV)ꢀ);ꢀE(VꢀvsꢀHg Cl /Hg,ꢀ1MꢀLiCl).ꢀꢀ
ꢀ
7
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European Journal of Inorganic Chemistry
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ꢀ
ꢀ
ReplacingꢀArꢀwithꢀCO
2
ꢀessentiallyꢀleadsꢀtoꢀanꢀincreaseꢀinꢀtheꢀelectrochemicalꢀresponseꢀbelowꢀ
-
2
1.5V,ꢀsuggestingꢀanꢀinteractionꢀbetweenꢀCO ꢀandꢀtheꢀreducedꢀcomplex.ꢀUponꢀadditionꢀofꢀupꢀtoꢀ5%ꢀ
water,ꢀtheꢀredoxꢀprocessesꢀbelowꢀ-1.25Vꢀagainꢀgainꢀinꢀintensityꢀandꢀappearꢀtoꢀbeꢀshiftedꢀtowardꢀlessꢀ
reducingꢀpotentialsꢀ(Figureꢀ4).ꢀWeꢀthusꢀperformedꢀanꢀelectrolysisꢀatꢀ-1.6V*(*ꢀfootnote:ꢀperformingꢀ
theꢀelectrolysisꢀatꢀ-1.4Vꢀresultedꢀinꢀveryꢀweakꢀactivity,ꢀwhileꢀatꢀ-1.8VꢀonlyꢀH
theꢀpresenceꢀofꢀ5%ꢀwaterꢀunderꢀaꢀCO ꢀatmosphere.ꢀTheꢀexperimentꢀled,ꢀafterꢀ5hꢀelectrolysis,ꢀtoꢀtheꢀ
detectionꢀofꢀH ꢀasꢀaꢀmajorꢀproductꢀ(120ꢀ10 mol,ꢀ12ꢀTON,ꢀ68ꢀ%ꢀfaradicꢀyield)ꢀwithꢀHCOO ꢀasꢀaꢀveryꢀ
2
ꢀcouldꢀbeꢀdetected)ꢀinꢀ
2
-
6ꢀ
-
2
-
6ꢀ
minorꢀ reductionꢀ productꢀ (8ꢀ 10 mol,ꢀ 0.8ꢀ TON,ꢀ 4.5ꢀ %ꢀ faradicꢀ yield).ꢀ Again,ꢀ uponꢀ reduction,ꢀ theꢀ
solutionꢀturnedꢀblue,ꢀindicatingꢀthatꢀsomeꢀofꢀelectricalꢀchargeꢀisꢀusedꢀtoꢀreduceꢀtheꢀPOMꢀskeleton,ꢀ
whichꢀcanꢀpartlyꢀexplainꢀtheꢀlowerꢀglobalꢀfaradicꢀyield,ꢀtogetherꢀwithꢀtheꢀformationꢀofꢀother,ꢀstillꢀ
unidentified,ꢀreductionꢀproducts.ꢀAsꢀaꢀpointꢀofꢀcomparison,ꢀweꢀperformedꢀtheꢀsameꢀexperimentꢀwithꢀ
+
-
-6ꢀ
[
Cp*Rh(III)(bpy)Cl] .ꢀInꢀourꢀconditions,ꢀtheꢀlatterꢀledꢀtoꢀtheꢀgenerationꢀofꢀHCOO ꢀ(180ꢀ10 mol,ꢀ18ꢀ
-
6ꢀ
2
TON,ꢀ60%ꢀfaradicꢀyield)ꢀasꢀaꢀmajorꢀproduct,ꢀtogetherꢀwithꢀH ꢀ(90ꢀ10 mol,ꢀ9ꢀTON,ꢀ30%ꢀfaradicꢀyield).ꢀꢀ
Thus,ꢀ replacingꢀ theꢀ bidentateꢀ bipyridineꢀ withꢀ aꢀ bidentateꢀ POMꢀ allowsꢀ forꢀ aꢀ largeꢀ reversalꢀ ofꢀ theꢀ
n+
selectivityꢀofꢀtheꢀꢀ[Cp*Rh(III)(L-L)] ꢀmolecularꢀcatalystꢀ(L-L=ꢀbpy,ꢀn=2,ꢀorꢀL-L=ꢀPOM,ꢀn=5)ꢀinꢀfavorꢀofꢀ
2
protonꢀreductionꢀoverꢀCO ꢀreduction.ꢀ
+
ꢀ
Theꢀactiveꢀspeciesꢀproposedꢀinꢀtheꢀelectro-assistedꢀreductionꢀofꢀCO
2
ꢀbyꢀ[Cp*Rh(III)(bpy)Cl] ꢀisꢀ
aꢀ hydrideꢀ obtainedꢀ afterꢀ theꢀ two-electronꢀ reductionꢀ ofꢀ theꢀ Rh(III)ꢀ centerꢀ andꢀ subsequentꢀ
[
19,63]
protonation,
ꢀ theꢀ followingꢀ stepꢀ beingꢀ theꢀ reductionꢀ ofꢀ theꢀ bpyꢀ ligand,ꢀ precedingꢀ theꢀ
3
-
incorporationꢀ ofꢀ CO
2
2 2
.ꢀ Inꢀ theꢀ caseꢀ ofꢀ [H PW11O39{Rh(III)Cp*(OH )}] ,ꢀ theꢀ protonationꢀ willꢀ alsoꢀ likelyꢀ
occurꢀatꢀtheꢀreducedꢀPOM,ꢀwhichꢀcouldꢀexplainꢀtheꢀchangeꢀinꢀselectivtyꢀofꢀtheꢀreaction.ꢀ
ꢀ
ꢀ
Metalꢀcomplexesꢀwithꢀpolypyridylꢀligandsꢀareꢀwithꢀcomplexesꢀofꢀmacrocyclicꢀligandsꢀamongꢀ
[
64]
2
theꢀ mostꢀ studiedꢀ molecularꢀ electrocatalystsꢀ forꢀ CO ꢀ reduction. ꢀ Sinceꢀ theꢀ earlyꢀ reportsꢀ onꢀ
[
65]
[9]
[
3
M(bpy)(CO) X]ꢀ(ꢀM=ꢀRe, ꢀMn )ꢀmanyꢀvariationsꢀonꢀtheꢀbpyꢀligandꢀhaveꢀbeenꢀdevisedꢀtoꢀassessꢀ
[
10,66]
[67,68]
[69]
stericꢀeffectsꢀ
ꢀꢀorꢀtheꢀeffectsꢀonꢀtheꢀcatalyticꢀactivityꢀofꢀaꢀphenolicꢀproton,
ꢀaꢀcharge ꢀorꢀaꢀ
[
70]
pendantꢀ Lewisꢀ base ꢀ inꢀ closeꢀ proximityꢀ ofꢀ theꢀ CO2ꢀ bindingꢀ site.ꢀ Enhancementꢀ ofꢀ theꢀ catalyticꢀ
efficiencyꢀisꢀgenerallyꢀobserved,ꢀsignificantꢀforꢀbulkyꢀligandsꢀthatꢀhinderꢀdimerization,ꢀoftenꢀmodestꢀ
inꢀtheꢀotherꢀcases.ꢀTheꢀelectronicꢀeffectsꢀofꢀelectron-donatingꢀorꢀelectron-withdrawingꢀsubstituentsꢀ
[
66,71]
onꢀ theꢀ bpyꢀ ligandꢀ areꢀ stillꢀ unclear.
ꢀ Inꢀ anꢀ exampleꢀ closelyꢀ relatedꢀ toꢀ thisꢀ study,ꢀ complexesꢀ
+
[
Cp*Ir(bpy-R,R’)Cl] ꢀpreparedꢀwithꢀvariousꢀunsymmetricallyꢀsubstitutedꢀbipyridineꢀligandsꢀwereꢀfoundꢀ
[
72]
2
toꢀ haveꢀ aꢀ moderateꢀ electrocatalyticꢀ activityꢀ inꢀ CO ꢀ reduction ꢀ butꢀ withꢀ noꢀ directꢀ correlationꢀ
ꢀ
8
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European Journal of Inorganic Chemistry
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betweenꢀtheꢀredoxꢀpotentialsꢀandꢀtheꢀcatalyticꢀactivity.ꢀRegardingꢀtheꢀreplacementꢀofꢀtheꢀbpyꢀligandꢀ
byꢀanotherꢀredoxꢀnon-innocentꢀligand,ꢀrationalizationꢀisꢀstillꢀmissing:ꢀnoneꢀofꢀtheꢀ[Re(N^N)(CO) X]ꢀꢀ
complexesꢀwithꢀN^Nꢀbeingꢀ2-pyridyl-1,2,3-triazoleꢀligandꢀꢀwasꢀfoundꢀtoꢀoutperformꢀtheꢀbenchmarkꢀ
3
[
73]
catalystꢀ [Re(bpy)(CO)
3
X], ꢀ whereasꢀ aꢀ Re-pyridyl-NHCꢀ speciesꢀ displaysꢀ aꢀ slightlyꢀ higherꢀ faradicꢀ
[
74]
[75]
efficiency ꢀ andꢀ someꢀ Re-pyridine-oxazolinesꢀ higherꢀ TOFꢀ butꢀ decreasedꢀ faradicꢀ efficiency;
ꢀ
[
76]
[77]
[
Mn(N^N)(CO)
3
X]ꢀ ꢀ whereꢀ N^Nꢀ standsꢀ forꢀ iminopyridines ꢀ orꢀ α-diimines ꢀ doꢀ catalyzeꢀ theꢀ
2
-
conversionꢀofꢀCO
2
3
ꢀtoꢀCOꢀandꢀCO ꢀbutꢀatꢀtheꢀcostꢀofꢀanꢀincreasedꢀoverpotential.ꢀTheseꢀexamplesꢀ
underlineꢀ thatꢀ moreꢀ structure-activityꢀ relationshipsꢀ studiesꢀ areꢀ neededꢀ toꢀ improveꢀ ourꢀ
understandingꢀ ofꢀ theꢀ relevantꢀ parametersꢀ andꢀ toꢀ findꢀ aꢀ goodꢀ balanceꢀ betweenꢀ decreasingꢀ theꢀ
[
78]
overpotentialꢀandꢀkeepingꢀsufficientꢀreducingꢀpowerꢀinꢀtheꢀredoxꢀnon-innocentꢀligand. ꢀFromꢀthisꢀ
pointꢀofꢀview,ꢀvacantꢀPOMsꢀwithꢀtunableꢀredoxꢀpropertiesꢀstillꢀdeserveꢀattentionꢀasꢀunconventionalꢀ
redoxꢀnon-innocentꢀligands.ꢀꢀ
ꢀ
Conclusionsꢀ
3
Inꢀthisꢀpaper,ꢀweꢀhaveꢀdescribedꢀtheꢀsynthesisꢀofꢀaꢀnewꢀorganometallicꢀderivativeꢀofꢀPOMs,ꢀ(TBA) [α-
IIIꢀ
H
2
PW11
O
39{Rh(III)Cp*(OH
electrochemicalꢀ responseꢀ inꢀ acetonitrileꢀ ofꢀ [α-H
severalꢀ reductionꢀ processes.ꢀ Thisꢀ electrochemicalꢀ behaviorꢀ wasꢀ modifiedꢀ inꢀ theꢀ presenceꢀ ofꢀ CO
stronglyꢀsuggestingꢀsomeꢀinteractionꢀwithꢀtheꢀPOMꢀderivativeꢀdespiteꢀtheꢀpresenceꢀofꢀaꢀcoordinatingꢀ
2
)}],ꢀ presentingꢀ anꢀ accessibleꢀ coordinationꢀ siteꢀ onꢀ theꢀ Rh center.ꢀ Theꢀ
3
-
2
PW11
O
39{Rh(III)Cp*(OH
2
)}] ꢀ isꢀ complex,ꢀ exhibitingꢀ
2
,ꢀ
6
-
solvent,ꢀ aꢀ clearꢀ improvementꢀ comparedꢀ toꢀ [CoSiW11
O39] .ꢀ However,ꢀ electro-assistedꢀ reductionꢀ ofꢀ
CO ꢀinꢀtheꢀpresenceꢀofꢀwaterꢀasꢀaꢀprotonꢀsourceꢀmainlyꢀledꢀtoꢀtheꢀcatalyticꢀformationꢀofꢀdihydrogen,ꢀ
2
withꢀformateꢀbeingꢀaꢀminorꢀproduct.ꢀꢀ
ꢀ
ExperimentalꢀSectionꢀ
Chemicalsꢀ
Analyticalꢀ gradeꢀ solventsꢀ wereꢀ purchasedꢀ fromꢀ Sigma-Aldrich.ꢀ Dichloromethaneꢀ andꢀ acetonitrileꢀ
wereꢀdistilledꢀoverꢀcalciumꢀhydrideꢀunderꢀargon.ꢀTetrabutylammoniumꢀhydrogensulfateꢀ(TBAHSO ,ꢀ
7%)ꢀ andꢀ trifluoroaceticꢀ acidꢀ (TFA)ꢀ wereꢀ purchasedꢀ fromꢀ Sigma-Aldrich,ꢀ Tetrabutylammoniumꢀ
hydroxydeꢀ(TBAOH/MeOH,ꢀ40ꢀwt%),ꢀTetrabutylammoniumꢀbromideꢀ(TBABr),ꢀTetrabutylammoniumꢀ
nitrateꢀ (TBANO )ꢀ andꢀ sodiumꢀ tetrafluoroborateꢀ (NaBF ,ꢀ 97%)ꢀ wereꢀ suppliedꢀ byꢀ Alpha-Aesar.ꢀ
,2,3,4,5-Pentamethylcyclopentadieneꢀ wasꢀ providedꢀ byꢀ Acrosꢀ Laboratories.ꢀ [(RhCp*Cl(µ-Cl)] ꢀ andꢀ
4
9
3
4
1
2
[
79,80]
[
RhCp*(bpy)Cl)].Clꢀꢀwereꢀsynthesizedꢀaccordingꢀtoꢀliteratureꢀprocedures.
ꢀꢀ
ꢀ
9
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European Journal of Inorganic Chemistry
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4 4
Tetrabutylammoniumꢀ tetrafluoroborateꢀ (TBABF )ꢀ wasꢀ preparedꢀ byꢀ mixingꢀ 200ꢀ mLꢀ ofꢀ 1.3ꢀ Mꢀ NaBF ꢀ
4
withꢀ200ꢀmLꢀofꢀ1MꢀTBAHSO ꢀinꢀwaterꢀunderꢀvigorousꢀstirring.ꢀAꢀwhiteꢀprecipitateꢀwasꢀformedꢀandꢀ
additionalꢀwaterꢀ(aboutꢀ400ꢀmL)ꢀwasꢀadded.ꢀTheꢀprecipitateꢀwasꢀfilteredꢀonꢀaꢀfritꢀandꢀwashedꢀuntilꢀ
wastewaterꢀreachedꢀaꢀpHꢀofꢀca.ꢀ5.ꢀTheꢀwhiteꢀpowderꢀwasꢀredissolvedꢀinꢀdichloromethaneꢀandꢀdriedꢀ
4
withꢀ MgSO .ꢀ Theꢀ organicꢀ phaseꢀ wasꢀ filteredꢀ andꢀ finallyꢀ evaporatedꢀ underꢀ vacuumꢀ toꢀ getꢀ aꢀ whiteꢀ
powderꢀstoredꢀunderꢀargon.ꢀ
Analyticalꢀmethodsꢀ
FT-IRꢀspectraꢀwereꢀrecordedꢀfromꢀKBrꢀpelletsꢀonꢀaꢀJASCOꢀFTIRꢀ4100ꢀspectrometer.ꢀTheꢀspectraꢀwereꢀ
-
1
recordedꢀwithꢀ16ꢀscansꢀwithꢀanꢀaccuracyꢀofꢀ4ꢀcm .ꢀUV-visibleꢀspectraꢀwereꢀrecordedꢀonꢀJascoꢀV-670,ꢀ
1
1
13
31
usingꢀquartzꢀcell.ꢀ H,ꢀ{ H}ꢀ- Cꢀandꢀ PꢀNMRꢀspectrumsꢀwereꢀrecordedꢀonꢀaꢀBrukerꢀAdvanceꢀIIꢀ300ꢀMHz.ꢀ
1
13
Hꢀ andꢀ Cꢀ NMRꢀ signalsꢀ wereꢀ referencedꢀ toꢀ theꢀ residualꢀ solventꢀ signalsꢀ andꢀ areꢀ givenꢀ relativeꢀ toꢀ
3
1
(
3 4 3
CH ) Si.ꢀꢀ PꢀNMRꢀisꢀreferencedꢀrelativeꢀtoꢀH PO4ꢀ(85%).ꢀElementalꢀanalysesꢀwereꢀperformedꢀatꢀICSN–
CNRSꢀ (Gif-sur-Yvette,ꢀ France).ꢀ Thermogravimetricꢀ analysesꢀ wereꢀ performedꢀ onꢀ TA-Instrumentꢀ SDTꢀ
Q600ꢀunderꢀdryꢀair.ꢀTheꢀhighꢀresolutionꢀESIꢀmassꢀspectraꢀwereꢀrecordedꢀusingꢀanꢀLTQꢀOrbitrapꢀhybridꢀ
massꢀspectrometerꢀ(ThermofisherꢀScientific,ꢀBremen,ꢀGermany)ꢀequippedꢀwithꢀanꢀexternalꢀESIꢀsourceꢀ
operatedꢀinꢀtheꢀnegativeꢀionꢀmode.ꢀꢀ
Synthesisꢀofꢀ(TBA)
5 2
[α-H PW11O39].ꢀ
[
81]
(
TBA) PW11O39]ꢀ wasꢀ preparedꢀ accordingꢀ toꢀ theꢀ literature ꢀ andꢀ theꢀ synthesisꢀ ofꢀ (TBA) [α-
4
[α-H
39]ꢀwasꢀadaptedꢀfromꢀliteratureꢀasꢀfollows: ꢀ(TBA)
dissolvedꢀinꢀacetonitrileꢀ(50ꢀmL)ꢀ(anyꢀinsolubleꢀproductꢀwasꢀfilteredꢀoff)ꢀandꢀ636ꢀµLꢀofꢀTBAOH/MeOHꢀ
40ꢀwt%,ꢀ0.636ꢀmmol,ꢀ1ꢀeq.)ꢀwasꢀaddedꢀdrop-wiseꢀwithꢀvigorousꢀstirring.ꢀTheꢀresultingꢀsolutionꢀwasꢀ
concentratedꢀtoꢀ20ꢀmLꢀandꢀ30ꢀmLꢀofꢀdiethylꢀetherꢀwereꢀadded.ꢀAꢀfirstꢀwhiteꢀprecipitate,ꢀcontainingꢀ
TBA) [α-H 39],ꢀwasꢀrecoveredꢀbyꢀcentrifugationꢀandꢀdiscarded.ꢀAnꢀadditionalꢀ100ꢀmLꢀofꢀdiethylꢀ
etherꢀwasꢀaddedꢀtoꢀtheꢀsolution,ꢀleadingꢀtoꢀprecipitationꢀofꢀaꢀwhiteꢀpowder,ꢀwhichꢀwasꢀrecoveredꢀbyꢀ
3
5
[
82]
H
2
PW11
O
4 3
[α-H PW11O39]ꢀ(2.45ꢀg;ꢀ0.636ꢀmmol)ꢀwasꢀ
(
(
4
3
PW11O
3
1
filtration,ꢀrinsedꢀthoroughlyꢀwithꢀdiethylꢀetherꢀandꢀdriedꢀunderꢀvacuum.ꢀYield:ꢀ1.80ꢀgꢀ(69%)ꢀ PꢀNMRꢀ
(
300ꢀMHz,ꢀCD CN,ꢀ20°C):ꢀδ=-11.50ꢀppm.ꢀ
3
Synthesisꢀofꢀ(TBA)
3
[α-H
2
PW11
O
39{Rh(III)Cp*(H
2 2
O)}].H O.ꢀ
1
03ꢀmgꢀ(166ꢀµmol,ꢀ0.66ꢀeq.)ꢀofꢀ[(RhCp*Cl
2
)
2
]ꢀandꢀ129ꢀmgꢀ(662ꢀµmol,ꢀ2.6ꢀeq.)ꢀofꢀAgBF ꢀwereꢀaddedꢀ
4
intoꢀaꢀseptumꢀclosedꢀ15mLꢀFalcon®ꢀtubeꢀpurgedꢀwithꢀargon.ꢀThen,ꢀ2ꢀmlꢀofꢀdryꢀdistilledꢀacetonitrileꢀ
wasꢀaddedꢀandꢀtheꢀmixtureꢀwasꢀsonicatedꢀforꢀ15ꢀminutes.ꢀTheꢀinitiallyꢀredꢀcloudyꢀsolutionꢀturnedꢀ
quicklyꢀ brightꢀ yellowꢀ whileꢀ aꢀ whiteꢀ powderꢀ precipitated.ꢀ Itꢀ wasꢀ removedꢀ byꢀ centrifugation,ꢀ andꢀꢀ
washedꢀ twiceꢀ withꢀ 3mLꢀ ofꢀ dichloromethane.ꢀ Theꢀ yellowꢀ organicꢀ phasesꢀ wereꢀ evaporatedꢀ underꢀ
vacuumꢀatꢀ55°Cꢀtoꢀremoveꢀexcessꢀsolvent.ꢀTheꢀyellowꢀcrystallineꢀproductꢀwasꢀthenꢀredissolvedꢀunderꢀ
ꢀ
10
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European Journal of Inorganic Chemistry
10.1002/ejic.201800454
argonꢀinꢀ20ꢀmLꢀofꢀdryꢀdistilledꢀdichloromethaneꢀandꢀaddedꢀdrop-wiseꢀwithꢀvigorousꢀstirringꢀunderꢀ
argonꢀtoꢀaꢀsolutionꢀofꢀ974ꢀmgꢀ(250ꢀµmol,ꢀ1ꢀeq.)ꢀofꢀ(TBA) [H 39]ꢀwithꢀ51.5ꢀmgꢀofꢀEt Nꢀ(510ꢀµmol,ꢀ
.1ꢀ eq.)ꢀ inꢀ 250ꢀ mLꢀ ofꢀ dichloromethane.ꢀ ꢀ Theꢀ resultingꢀ orangeꢀ solutionꢀ wasꢀ stirredꢀ underꢀ argonꢀ
overnight.ꢀꢀ
5
2
PW11
O
3
2
AꢀdilutedꢀsolutionꢀofꢀTFAꢀinꢀdichloromethaneꢀ(510ꢀµmol,ꢀ2.1ꢀeq.,ꢀ0,1gꢀTFAꢀ/ꢀ100mL)ꢀwasꢀaddedꢀslowlyꢀ
withꢀvigorousꢀstirringꢀtoꢀtheꢀpreviousꢀorangeꢀsolution.ꢀAnꢀorangeꢀprecipitateꢀwasꢀformedꢀandꢀfilteredꢀ
onꢀaꢀfritꢀ(porosityꢀ4),ꢀrinsedꢀwithꢀdichloromethane,ꢀthenꢀwithꢀdiethylꢀetherꢀandꢀdriedꢀunderꢀvacuum.ꢀ
Aꢀfineꢀyellow-orangeꢀpowderꢀwasꢀobtainedꢀ(m=ꢀ600ꢀmgꢀYield:ꢀ65%).ꢀ
Theꢀcrudeꢀproductꢀwasꢀthenꢀdissolvedꢀinꢀ35ꢀmLꢀofꢀMeNO
separatedꢀbyꢀdecantation.ꢀTheꢀoperationꢀwasꢀrepeatedꢀuntilꢀtheꢀwashꢀwaterꢀretainsꢀitsꢀinitialꢀpH.ꢀ
Brownꢀimpuritiesꢀthatꢀappearꢀafterꢀtheꢀfirstꢀwashingꢀareꢀfilteredꢀoff).ꢀTheꢀorganicꢀphaseꢀwasꢀthenꢀ
2
,ꢀandꢀwashedꢀwithꢀ10ꢀmLꢀofꢀwaterꢀandꢀ
(
concentratedꢀtoꢀ10ꢀmLꢀunderꢀvacuumꢀatꢀ55°Cꢀthenꢀpooredꢀdropwiseꢀinꢀ90ꢀmLꢀofꢀdiethylꢀetherꢀwithꢀ
vigorousꢀstirring.ꢀTheꢀorangeꢀpowderꢀwasꢀrecoveredꢀbyꢀcentrifugation,ꢀwashedꢀwithꢀdiethylꢀetherꢀandꢀ
driedꢀunderꢀvacuumꢀ(mꢀ=ꢀ500mg,finalꢀyield:ꢀ55ꢀ%).ꢀAllꢀourꢀattemptsꢀtoꢀgrowꢀsingleꢀcrystalꢀofꢀthisꢀ
compoundꢀwereꢀunsucessfull.ꢀ
3
1
1
PꢀNMRꢀ(300ꢀMHz,ꢀCD
3
CN,ꢀ20ꢀ°C)ꢀδ=ꢀ-12.2ꢀppm;ꢀ HꢀNMRꢀ(300ꢀMHz,ꢀCD
),ꢀ1.77ꢀ(s,ꢀ15H,ꢀCp*-CH ),ꢀ1.64ꢀ(m,ꢀ24H,ꢀNCH CH ),ꢀ1.40ꢀ(sext,ꢀ24H,ꢀNCH
)ꢀppm;ꢀ CꢀNMRꢀ(300ꢀMHz,ꢀCD CN,ꢀ20ꢀ°C):ꢀδ=ꢀ59.32ꢀ(TBA),ꢀ24.37ꢀ(TBA),ꢀ20.32ꢀ(TBA),ꢀ
3
CN,ꢀ20ꢀ°C):ꢀδ=ꢀ3.13ꢀ(m,ꢀ24H,ꢀ
NCH
NCH
2
2
3
2
2
2 2 2
CH CH ),ꢀ0.98ꢀ(t,ꢀ36H,ꢀ
1
3
CH
2
CH
2
CH
3
3
-
1
1
3
3.84ꢀ(TBA),ꢀ9.37ꢀ(Cp*-CH )ꢀppm;ꢀFT-IRꢀ(KBrꢀpellet,ꢀinꢀcm ):ꢀ2961ꢀ(w,ꢀC-H,ꢀTBAꢀandꢀCp*),ꢀ2934ꢀ(w,ꢀC-
ꢀ
H,ꢀTBA andꢀCp*),ꢀ2873ꢀ(w,ꢀC-H,ꢀTBAꢀandꢀCp*),ꢀ1483ꢀ(w,ꢀTBAꢀandꢀCp*),ꢀ1381ꢀ(w,Cp*),ꢀ1155ꢀ(w),ꢀ1105ꢀ
(
w),ꢀ1079ꢀ(w,ꢀP-O),ꢀ1048ꢀ(m,ꢀP-O),ꢀ970ꢀ(sh,ꢀW=O
t t
),ꢀ957ꢀ(s,ꢀW=O ),ꢀ890ꢀ(m,ꢀW-O-W),ꢀ813ꢀ(s,ꢀW-O-W),ꢀ
[
57,60]
7
51ꢀ(sh,ꢀW-O-W),ꢀ594ꢀ(w,ꢀW-O-W),ꢀ522ꢀ(w,ꢀW-O-W),ꢀ379ꢀ(m,ꢀW-O-W);
ꢀUV-vis:ꢀε(256ꢀnm)ꢀ=ꢀ42ꢀ970ꢀ
-
1
-1
-1
-1 ꢀ
L.mol .cm ;ꢀε(400ꢀnm)ꢀ=ꢀ2ꢀ924ꢀL.mol .cm ; Elementalꢀanalysisꢀ(calculatedꢀforꢀC58 41PRhW11):ꢀC:ꢀ
129 3
H N O
1
ꢀ
8.93%ꢀ(18.93%);ꢀH:ꢀ3.38%ꢀ(3.53%);ꢀN:ꢀ0.96%ꢀ(1.14ꢀ%).ꢀ
Electrochemicalꢀexperimentsꢀ
Analyticalꢀ experimentsꢀ wereꢀ carriedꢀ outꢀ withꢀ aꢀ Princetonꢀ Appliedꢀ Researchꢀ Potentiostatꢀ (Modelꢀ
63A).ꢀTheꢀstudiesꢀwereꢀperformedꢀusingꢀaꢀclassicalꢀthree-electrodesꢀcell.ꢀꢀ
2
AcetonitrileꢀcontainingꢀTBABF
4
ꢀ(0.1M)ꢀwasꢀusedꢀasꢀelectrolyticꢀsolution.ꢀAllꢀstudiedꢀsolutionsꢀwereꢀ
purgedꢀpriorꢀmeasurementsꢀbyꢀbubblingꢀinertꢀgasꢀorꢀCO
2
ꢀforꢀ10ꢀminꢀforꢀcyclicꢀvoltammetryꢀ(CV)ꢀorꢀ20ꢀ
minꢀforꢀelectrolysisꢀpriorꢀmeasurements,ꢀtheꢀgasꢀbeingꢀbeforehandꢀbubbledꢀinꢀacetonitrileꢀsoꢀasꢀtoꢀ
limitꢀsolventꢀevaporation.ꢀꢀ
ꢀ
11
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European Journal of Inorganic Chemistry
10.1002/ejic.201800454
Cyclicꢀ voltammetryꢀ wasꢀ performedꢀ atꢀ aꢀ scanꢀ rateꢀ ofꢀ 100ꢀ mV/s.ꢀ Aꢀ glassyꢀ carbonꢀ electrodeꢀ (3ꢀ mmꢀ
diameter)ꢀwasꢀusedꢀasꢀworkingꢀelectrode,ꢀpolishedꢀwithꢀaꢀ¼ꢀµmꢀdiamondꢀsuspension.ꢀTheꢀcounterꢀ
electrodeꢀwasꢀaꢀplatinumꢀwireꢀandꢀaꢀCalomelꢀ(1MꢀLiCl)ꢀelectrodeꢀseparatedꢀbyꢀaꢀVycorꢀtipꢀwasꢀusedꢀ
asꢀreferenceꢀ(RadiometerꢀAnalytical,ꢀFrance)ꢀ.ꢀꢀ
Bulkꢀ electrolysisꢀ experimentsꢀ wereꢀ carriedꢀ outꢀ inꢀ aꢀ customꢀ madeꢀ two-compartmentꢀ cell.ꢀ Aꢀ glassyꢀ
carbonꢀelectrodeꢀ(13ꢀmmꢀdiameter,ꢀOrigalys)ꢀwasꢀusedꢀasꢀtheꢀworkingꢀelectrodeꢀandꢀaꢀCalomelꢀ1Mꢀ
LiClꢀreferenceꢀelectrodeꢀ(RadiometerꢀAnalytical,ꢀFrance)ꢀwasꢀseparatedꢀbyꢀaꢀVycorꢀtip.ꢀTheꢀcounterꢀ
electrodeꢀusedꢀwasꢀaꢀplatinumꢀwireꢀseparatedꢀfromꢀtheꢀworkingꢀelectrodeꢀbyꢀaꢀfritꢀ(porosityꢀ4).ꢀTheꢀ
volumeꢀ ofꢀ theꢀ solutionꢀ usedꢀ inꢀ theꢀ cathodicꢀ compartmentꢀ wasꢀ 20mLꢀ (6ꢀ mLꢀ inꢀ theꢀ anodicꢀ
compartment)ꢀ andꢀ theꢀ typicalꢀ headspaceꢀ volumeꢀ wasꢀ 46mL.ꢀ Saint-Gobainꢀ Performanceꢀ Plasticsꢀ
Franceꢀ naturalꢀ rubberꢀ foldingꢀ skirtꢀ stoppersꢀ wereꢀ usedꢀ toꢀ closeꢀ theꢀ cell.ꢀ Aꢀ Bio-Logicꢀ SPꢀ 300ꢀ
potentiostatꢀ connectedꢀ toꢀ aꢀ boosterꢀ cardꢀ wasꢀ used.ꢀ Solutionsꢀ wereꢀ constantlyꢀ stirredꢀ throughoutꢀ
bulkꢀelectrolysisꢀexperiments.ꢀ
Analysisꢀofꢀelectrolysisꢀproductsꢀ
H
2
ꢀmeasurementsꢀwereꢀperformedꢀbyꢀgasꢀchromatographyꢀonꢀaꢀShimadzuꢀGC-2014ꢀequippedꢀwithꢀaꢀ
Quadrexꢀcolumn,ꢀaꢀThermalꢀConductivityꢀDetectorꢀandꢀusingꢀN ꢀasꢀaꢀcarrierꢀgas.ꢀOtherꢀgasesꢀ(CO,ꢀ
CH )ꢀwereꢀmeasuredꢀusingꢀaꢀShimadzuꢀGC-2010ꢀPlusꢀgasꢀchromatography,ꢀfittedꢀwithꢀaꢀRestekꢀShinꢀ
2
4
Carbonꢀ column,ꢀ heliumꢀ carrierꢀ gas,ꢀ aꢀ methanizerꢀ andꢀ aꢀ Flameꢀ Ionizationꢀ Detector.ꢀ Gasꢀ
chromatographyꢀ calibrationsꢀ wereꢀ madeꢀ byꢀ samplingꢀ knownꢀ volumesꢀ ofꢀ theꢀ variousꢀ gases.ꢀ Theꢀ
typicalꢀvolumeꢀofꢀgasꢀinjectedꢀwasꢀ50ꢀµL.ꢀꢀ
Formateꢀ andꢀ oxalateꢀ concentrationsꢀ wereꢀ determinedꢀ byꢀ ionicꢀ chromatographyꢀ usingꢀ aꢀ Metrohmꢀ
8
83ꢀBasicꢀICꢀplusꢀionicꢀexchangeꢀchromatographyꢀinstrument,ꢀaꢀMetrosepꢀAꢀSuppꢀ5ꢀcolumnꢀandꢀaꢀ
conductivityꢀdetector.ꢀAꢀtypicalꢀmeasurementꢀrequiredꢀtheꢀsamplingꢀofꢀ1ꢀmLꢀofꢀsolution,ꢀfollowedꢀbyꢀ
-
1
aꢀ100ꢀfoldꢀdilutionꢀinꢀdeionisedꢀ18ꢀMΩꢀcm ꢀwaterꢀandꢀdirectꢀinjectionꢀofꢀ20ꢀµLꢀintoꢀtheꢀinstrument.ꢀ
MethanolꢀwasꢀassessedꢀusingꢀaꢀShimadzuꢀGC-2010ꢀPlusꢀgasꢀchromatographyꢀfittedꢀwithꢀaꢀZB-WAXꢀ
Plusꢀcolumn,ꢀheliumꢀasꢀaꢀcarrierꢀgasꢀandꢀaꢀflameꢀionizationꢀdetector.ꢀꢀ
Formaldehydeꢀ concentrationꢀ wasꢀ assessedꢀ usingꢀ theꢀ Nashꢀ colorimetricꢀ testꢀ usingꢀ aꢀ V-670ꢀ Jascoꢀ
Spectrophotometerꢀinstrument.ꢀ
ꢀ
Acknowledgmentsꢀ
ꢀ
12
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European Journal of Inorganic Chemistry
10.1002/ejic.201800454
ThisꢀworkꢀwasꢀsupportedꢀbyꢀtheꢀFrenchꢀNationalꢀResearchꢀAgencyꢀ(ANR,ꢀCarBioRedꢀANR-12-BS07-
024-03).ꢀ Weꢀ thankꢀ Pr.ꢀ M.ꢀ Fontecaveꢀ andꢀ Dr.ꢀ P.ꢀ Simonꢀ (Laboratoireꢀ deꢀ Chimieꢀ desꢀ Processusꢀ
0
Biologiques,ꢀUMRꢀ8229ꢀCNRS,ꢀCollègeꢀdeꢀFrance,ꢀSorbonneꢀUniversity,ꢀPSLꢀResearchꢀUniversity)ꢀforꢀ
accessꢀtoꢀtheirꢀanalyticalꢀplatform.ꢀ
ꢀ
Keywords:ꢀ Polyoxometalates,ꢀ organometallicꢀ derivative,ꢀ carbonꢀ dioxideꢀ reduction,ꢀ redoxꢀ non-
innocentꢀligandꢀ
ꢀ
ꢀ
ꢀ
ꢀ
13
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European Journal of Inorganic Chemistry
10.1002/ejic.201800454
Referencesꢀ
[
[
1]ꢀ ©ꢀOECD/IEA,ꢀKeyꢀWorldꢀEnergyꢀStatistics,ꢀIEAꢀPublishing,ꢀ2016.ꢀ
2]ꢀ R.ꢀAmirante,ꢀE.ꢀCassone,ꢀE.ꢀDistaso,ꢀP.ꢀTamburrano,ꢀEnergyꢀConvers.ꢀManag.ꢀ2017,ꢀ132,ꢀ372–
87.ꢀ
3
[
[
[
[
[
3]ꢀ C.ꢀP.ꢀGrey,ꢀJ.ꢀM.ꢀTarascon,ꢀNat.ꢀMater.ꢀ2016,ꢀ16,ꢀ45–56.ꢀ
4]ꢀ N.ꢀArmaroli,ꢀV.ꢀBalzani,ꢀChemSusChemꢀ2011,ꢀ4,ꢀ21–36.ꢀ
5]ꢀ M.ꢀRobert,ꢀACSꢀEnergyꢀLett.ꢀ2016,ꢀ1,ꢀ281–282.ꢀ
6]ꢀ C.ꢀCostentin,ꢀM.ꢀRobert,ꢀJ.-M.ꢀSavéant,ꢀChemꢀSocꢀRevꢀ2013,ꢀ42,ꢀ2423–2436.ꢀ
7]ꢀ A.ꢀM.ꢀAppel,ꢀJ.ꢀE.ꢀBercaw,ꢀA.ꢀB.ꢀBocarsly,ꢀH.ꢀDobbek,ꢀD.ꢀL.ꢀDuBois,ꢀM.ꢀDupuis,ꢀJ.ꢀG.ꢀFerry,ꢀE.ꢀ
Fujita,ꢀ R.ꢀ Hille,ꢀ P.ꢀ J.ꢀ A.ꢀ Kenis,ꢀ C.ꢀ A.ꢀ Kerfeld,ꢀ R.ꢀ H.ꢀ Morris,ꢀ C.ꢀ H.ꢀ F.ꢀ Peden,ꢀ A.ꢀ R.ꢀ Portis,ꢀ S.ꢀ W.ꢀ
Ragsdale,ꢀT.ꢀB.ꢀRauchfuss,ꢀJ.ꢀN.ꢀH.ꢀReek,ꢀL.ꢀC.ꢀSeefeldt,ꢀR.ꢀK.ꢀThauer,ꢀG.ꢀL.ꢀWaldrop,ꢀChem.ꢀRev.ꢀ
2
013,ꢀ113,ꢀ6621–6658.ꢀ
[
[
8]ꢀ H.ꢀTakeda,ꢀC.ꢀCometto,ꢀO.ꢀIshitani,ꢀM.ꢀRobert,ꢀACSꢀCatal.ꢀ2017,ꢀ7,ꢀ70–88.ꢀ
9]ꢀ M.ꢀBourrez,ꢀF.ꢀMolton,ꢀS.ꢀChardon-Noblat,ꢀA.ꢀDeronzier,ꢀAngew.ꢀChem.ꢀInt.ꢀEd.ꢀ2011,ꢀ50,ꢀ9903–
9
906.ꢀ
[
10]ꢀ M.ꢀD.ꢀSampson,ꢀA.ꢀD.ꢀNguyen,ꢀK.ꢀA.ꢀGrice,ꢀC.ꢀE.ꢀMoore,ꢀA.ꢀL.ꢀRheingold,ꢀC.ꢀP.ꢀKubiak,ꢀ J.ꢀAm.ꢀ
Chem.ꢀSoc.ꢀ2014,ꢀ136,ꢀ5460–5471.ꢀ
[
[
[
[
[
[
11]ꢀ B.ꢀD.ꢀSteffey,ꢀC.ꢀJ.ꢀCurtis,ꢀD.ꢀL.ꢀDuBois,ꢀOrganometallicsꢀ1995,ꢀ14,ꢀ4937–4943.ꢀ
12]ꢀ C.ꢀCostentin,ꢀS.ꢀDrouet,ꢀM.ꢀRobert,ꢀJ.-M.ꢀSavéant,ꢀScienceꢀ2012,ꢀ338,ꢀ90–94.ꢀ
13]ꢀ I.ꢀAzcarate,ꢀC.ꢀCostentin,ꢀM.ꢀRobert,ꢀJ.-M.ꢀSavéant,ꢀJ.ꢀPhys.ꢀChem.ꢀCꢀ2016,ꢀ120,ꢀ28951–28960.ꢀ
14]ꢀ I.ꢀAzcarate,ꢀC.ꢀCostentin,ꢀM.ꢀRobert,ꢀJ.-M.ꢀSavéant,ꢀJ.ꢀAm.ꢀChem.ꢀSoc.ꢀ2016,ꢀ138,ꢀ16639–16644.ꢀ
15]ꢀ C.ꢀCostentin,ꢀM.ꢀRobert,ꢀJ.-M.ꢀSavéant,ꢀA.ꢀTatin,ꢀProc.ꢀNatl.ꢀAcad.ꢀSci.ꢀ2015,ꢀ112,ꢀ6882–6886.ꢀ
16]ꢀ A.ꢀTatin,ꢀC.ꢀComminges,ꢀB.ꢀKokoh,ꢀC.ꢀCostentin,ꢀM.ꢀRobert,ꢀJ.-M.ꢀSavéant,ꢀProc.ꢀNatl.ꢀAcad.ꢀSci.ꢀ
2
016,ꢀ113,ꢀ5526–5529.ꢀ
[
[
[
[
[
[
[
17]ꢀ A.ꢀTaheri,ꢀL.ꢀA.ꢀBerben,ꢀChemꢀCommunꢀ2016,ꢀ52,ꢀ1768–1777.ꢀ
18]ꢀ T.ꢀC.ꢀJohnson,ꢀD.ꢀJ.ꢀMorris,ꢀM.ꢀWills,ꢀChemꢀSocꢀRevꢀ2010,ꢀ39,ꢀ81–88.ꢀ
19]ꢀ C.ꢀCaix,ꢀS.ꢀChardon-Noblat,ꢀA.ꢀDeronzier,ꢀJ.ꢀElectroanal.ꢀChem.ꢀ1997,ꢀ434,ꢀ163–170.ꢀ
20]ꢀ C.ꢀW.ꢀMachan,ꢀM.ꢀD.ꢀSampson,ꢀC.ꢀP.ꢀKubiak,ꢀJ.ꢀAm.ꢀChem.ꢀSoc.ꢀ2015,ꢀ137,ꢀ8564–8571.ꢀ
21]ꢀ J.-M.ꢀSavéant,ꢀChem.ꢀRev.ꢀ2008,ꢀ108,ꢀ2348–2378.ꢀ
22]ꢀ P.ꢀKang,ꢀT.ꢀJ.ꢀMeyer,ꢀM.ꢀBrookhart,ꢀChem.ꢀSci.ꢀ2013,ꢀ4,ꢀ3497.ꢀ
23]ꢀ S.ꢀ Roy,ꢀ B.ꢀ Sharma,ꢀ J.ꢀ Pécaut,ꢀ P.ꢀ Simon,ꢀ M.ꢀ Fontecave,ꢀ P.ꢀ D.ꢀ Tran,ꢀ E.ꢀ Derat,ꢀ V.ꢀ Artero,ꢀ J.ꢀ Am.ꢀ
Chem.ꢀSoc.ꢀ2017,ꢀ139,ꢀ3685–3696.ꢀ
[
[
[
24]ꢀ K.ꢀKobayashi,ꢀK.ꢀTanaka,ꢀPhys.ꢀChem.ꢀChem.ꢀPhys.ꢀ2014,ꢀ16,ꢀ2240.ꢀ
25]ꢀ H.ꢀRao,ꢀL.ꢀC.ꢀSchmidt,ꢀJ.ꢀBonin,ꢀM.ꢀRobert,ꢀNatureꢀ2017,ꢀ548,ꢀ74–77.ꢀ
26]ꢀ C.ꢀL.ꢀHill,ꢀinꢀCompr.ꢀCoord.ꢀChem.ꢀIIꢀ(Eds.:ꢀJ.A.ꢀMcCleverty,ꢀT.J.ꢀMeyer),ꢀPergamon,ꢀOxford,ꢀ2003,ꢀ
pp.ꢀ679–759.ꢀ
[
[
[
[
[
[
[
[
[
27]ꢀ J.ꢀM.ꢀClemente-Juan,ꢀE.ꢀCoronado,ꢀA.ꢀGaita-Arino,ꢀChemꢀSocꢀRevꢀ2012,ꢀ41,ꢀ7464–7478.ꢀ
28]ꢀ H.ꢀN.ꢀMiras,ꢀJ.ꢀYan,ꢀD.-L.ꢀLong,ꢀL.ꢀCronin,ꢀChemꢀSocꢀRevꢀ2012,ꢀ41,ꢀ7403–7430.ꢀ
29]ꢀ Y.-F.ꢀSong,ꢀR.ꢀTsunashima,ꢀChemꢀSocꢀRevꢀ2012,ꢀ41,ꢀ7384–7402.ꢀ
30]ꢀ G.ꢀIzzet,ꢀF.ꢀVolatron,ꢀA.ꢀProust,ꢀChem.ꢀRec.ꢀ2016,ꢀ17,ꢀ250–266.ꢀ
31]ꢀ B.ꢀHasenknopf,ꢀFront.ꢀBiosci.ꢀJ.ꢀVirtualꢀLibr.ꢀ2005,ꢀ10,ꢀ275–287.ꢀ
32]ꢀ M.ꢀAureliano,ꢀG.ꢀFraqueza,ꢀC.ꢀA.ꢀOhlin,ꢀDaltonꢀTrans.ꢀ2013,ꢀ42,ꢀ11770–11777.ꢀ
33]ꢀ N.ꢀGao,ꢀH.ꢀSun,ꢀK.ꢀDong,ꢀJ.ꢀRen,ꢀT.ꢀDuan,ꢀC.ꢀXu,ꢀX.ꢀQu,ꢀNat.ꢀCommun.ꢀ2014,ꢀ5,ꢀ3422.ꢀ
34]ꢀ M.ꢀSadakane,ꢀE.ꢀSteckhan,ꢀChem.ꢀRev.ꢀ1998,ꢀ98,ꢀ219–238.ꢀ
35]ꢀ R.ꢀLiu,ꢀG.ꢀZhang,ꢀH.ꢀCao,ꢀS.ꢀZhang,ꢀY.ꢀXie,ꢀA.ꢀHaider,ꢀU.ꢀKortz,ꢀB.ꢀChen,ꢀN.ꢀS.ꢀDalal,ꢀY.ꢀZhao,ꢀL.ꢀZhi,ꢀ
C.-X.ꢀWu,ꢀL.-K.ꢀYan,ꢀZ.ꢀSu,ꢀB.ꢀKeita,ꢀEnergyꢀEnv.ꢀSciꢀ2016,ꢀ9,ꢀ1012–1023.ꢀ
36]ꢀ J.ꢀE.ꢀToth,ꢀF.ꢀC.ꢀAnson,ꢀJ.ꢀAm.ꢀChem.ꢀSoc.ꢀ1989,ꢀ111,ꢀ2444–2451.ꢀ
37]ꢀ S.ꢀDong,ꢀM.ꢀLiu,ꢀJ.ꢀElectroanal.ꢀChem.ꢀ1994,ꢀ372,ꢀ95–100.ꢀ
[
[
[
[
38]ꢀ B.ꢀKeita,ꢀE.ꢀAbdeljalil,ꢀL.ꢀNadjo,ꢀR.ꢀContant,ꢀR.ꢀBelgiche,ꢀElectrochem.ꢀCommun.ꢀ2001,ꢀ3,ꢀ56–62.ꢀ
39]ꢀ B.ꢀKeita,ꢀL.ꢀNadjo,ꢀJ.ꢀMol.ꢀCatal.ꢀChem.ꢀ2007,ꢀ262,ꢀ190–215.ꢀ
ꢀ
14
This article is protected by copyright. All rights reserved.

European Journal of Inorganic Chemistry
10.1002/ejic.201800454
[
40]ꢀ S.ꢀImar,ꢀC.ꢀMaccato,ꢀC.ꢀDickinson,ꢀF.ꢀLaffir,ꢀM.ꢀVagin,ꢀT.ꢀMcCormac,ꢀLangmuirꢀ2015,ꢀ31,ꢀ2584–
592.ꢀ
41]ꢀ T.ꢀYamase,ꢀM.ꢀSugeta,ꢀInorg.ꢀChim.ꢀActaꢀ1990,ꢀ172,ꢀ131–134.ꢀ
42]ꢀ A.ꢀM.ꢀKhenkin,ꢀI.ꢀEfremenko,ꢀL.ꢀWeiner,ꢀJ.ꢀM.ꢀL.ꢀMartin,ꢀR.ꢀNeumann,ꢀChem.ꢀ-ꢀEur.ꢀJ.ꢀ2010,ꢀ16,ꢀ
356–1364.ꢀ
2
[
[
1
[
[
[
[
43]ꢀ S.ꢀ H.ꢀ Szczepankiewic,ꢀ C.ꢀ M.ꢀ Ippolito,ꢀ B.ꢀ P.ꢀ Santora,ꢀ T.ꢀ J.ꢀ Vanꢀ deꢀ Ven,ꢀ G.ꢀ A.ꢀ Ippolito,ꢀ L.ꢀ
Fronckowiak,ꢀF.ꢀWiatrowski,ꢀT.ꢀPower,ꢀM.ꢀKozik,ꢀInorg.ꢀChem.ꢀ1998,ꢀ37,ꢀ4344–4352.ꢀ
44]ꢀ J.ꢀPaul,ꢀM.ꢀPage,ꢀP.ꢀSauers,ꢀK.ꢀErtel,ꢀC.ꢀPasternak,ꢀW.ꢀLin,ꢀM.ꢀKozik,ꢀinꢀPolyoxometalateꢀChem.ꢀ
Nano-Compos.ꢀDes.,ꢀT.ꢀYamase,ꢀM.ꢀPope,ꢀUSA,ꢀ2002,ꢀpp.ꢀ205–215.ꢀ
45]ꢀ M.ꢀGirardi,ꢀS.ꢀBlanchard,ꢀS.ꢀGriveau,ꢀP.ꢀSimon,ꢀM.ꢀFontecave,ꢀF.ꢀBedioui,ꢀA.ꢀProust,ꢀEur.ꢀJ.ꢀInorg.ꢀ
Chem.ꢀ2015,ꢀ22,ꢀ3642–3648.ꢀ
46]ꢀ S.ꢀDas,ꢀS.ꢀBiswas,ꢀT.ꢀBalaraju,ꢀS.ꢀBarman,ꢀR.ꢀPochamoni,ꢀS.ꢀRoy,ꢀJ.ꢀMater.ꢀChem.ꢀAꢀ2016,ꢀ4,ꢀ8875–
8
887.ꢀ
[
[
[
[
[
[
[
47]ꢀ J.ꢀEttedgui,ꢀY.ꢀDiskin-Posner,ꢀL.ꢀWeiner,ꢀR.ꢀNeumann,ꢀJ.ꢀAm.ꢀChem.ꢀSoc.ꢀ2011,ꢀ133,ꢀ188–190.ꢀ
48]ꢀ E.ꢀHaviv,ꢀL.ꢀJ.ꢀW.ꢀShimon,ꢀR.ꢀNeumann,ꢀChem.ꢀ-ꢀEur.ꢀJ.ꢀ2017,ꢀ23,ꢀ92–95.ꢀ
49]ꢀ S.-X.ꢀGuo,ꢀD.ꢀR.ꢀMacFarlane,ꢀJ.ꢀZhang,ꢀChemSusChemꢀ2016,ꢀ9,ꢀ80–87.ꢀ
50]ꢀ J.ꢀF.ꢀW.ꢀKeana,ꢀM.ꢀD.ꢀOgan,ꢀJ.ꢀAm.ꢀChem.ꢀSoc.ꢀ1986,ꢀ108,ꢀ7951–7957.ꢀ
51]ꢀ P.ꢀGouzerh,ꢀA.ꢀProust,ꢀChem.ꢀRev.ꢀ1998,ꢀ98,ꢀ77–112.ꢀ
52]ꢀ P.ꢀGouzerh,ꢀR.ꢀVillanneau,ꢀR.ꢀDelmont,ꢀA.ꢀProust,ꢀChem.ꢀ–ꢀEur.ꢀJ.ꢀ2000,ꢀ6,ꢀ1184–1192.ꢀ
53]ꢀ L.-H.ꢀBi,ꢀG.ꢀAl-Kadamany,ꢀE.ꢀV.ꢀChubarova,ꢀM.ꢀH.ꢀDickman,ꢀL.ꢀChen,ꢀD.ꢀS.ꢀGopala,ꢀR.ꢀM.ꢀRichards,ꢀ
B.ꢀKeita,ꢀL.ꢀNadjo,ꢀH.ꢀJaensch,ꢀG.ꢀMathys,ꢀU.ꢀKortz,ꢀInorg.ꢀChem.ꢀ2009,ꢀ48,ꢀ10068–10077.ꢀ
54]ꢀ N.ꢀH.ꢀNsouli,ꢀE.ꢀV.ꢀChubarova,ꢀR.ꢀAl-Oweini,ꢀB.ꢀS.ꢀBassil,ꢀM.ꢀSadakane,ꢀU.ꢀKortz,ꢀEur.ꢀJ.ꢀInorg.ꢀ
Chem.ꢀ2013,ꢀ2013,ꢀ1742–1747.ꢀ
[
[
55]ꢀ P.ꢀA.ꢀAbramov,ꢀM.ꢀN.ꢀSokolov,ꢀS.ꢀFloquet,ꢀM.ꢀHaouas,ꢀF.ꢀTaulelle,ꢀE.ꢀCadot,ꢀE.ꢀV.ꢀPeresypkina,ꢀA.ꢀ
V.ꢀVirovets,ꢀC.ꢀVicent,ꢀN.ꢀB.ꢀKompankov,ꢀA.ꢀA.ꢀZhdanov,ꢀO.ꢀV.ꢀShuvaeva,ꢀV.ꢀP.ꢀFedin,ꢀInorg.ꢀChem.ꢀ
2
014,ꢀ53,ꢀ12791–12798.ꢀ
[
[
[
[
56]ꢀ P.ꢀA.ꢀAbramov,ꢀM.ꢀN.ꢀSokolov,ꢀA.ꢀV.ꢀVirovets,ꢀS.ꢀFloquet,ꢀM.ꢀHaouas,ꢀF.ꢀTaulelle,ꢀE.ꢀCadot,ꢀC.ꢀ
Vicent,ꢀV.ꢀP.ꢀFedin,ꢀDaltonꢀTrans.ꢀ2015,ꢀ44,ꢀ2234–2239.ꢀ
57]ꢀ V.ꢀArtero,ꢀD.ꢀLaurencin,ꢀR.ꢀVillanneau,ꢀR.ꢀThouvenot,ꢀP.ꢀHerson,ꢀP.ꢀGouzerh,ꢀA.ꢀProust,ꢀInorg.ꢀ
Chem.ꢀ2005,ꢀ44,ꢀ2826–2835.ꢀ
58]ꢀ C.ꢀ Caix,ꢀ S.ꢀ Chardon-Noblat,ꢀ A.ꢀ Deronzier,ꢀ J.-C.ꢀ Moutet,ꢀ S.ꢀ Tingry,ꢀ J.ꢀ Organomet.ꢀ Chem.ꢀ 1997,ꢀ
5
40,ꢀ105–111.ꢀ
59]ꢀ M.ꢀ B.ꢀ Chambers,ꢀ X.ꢀ Wang,ꢀ N.ꢀ Elgrishi,ꢀ C.ꢀ H.ꢀ Hendon,ꢀ A.ꢀ Walsh,ꢀ J.ꢀ Bonnefoy,ꢀ J.ꢀ Canivet,ꢀ E.ꢀ A.ꢀ
Quadrelli,ꢀD.ꢀFarrusseng,ꢀC.ꢀMellot-Draznieks,ꢀM.ꢀFontecave,ꢀChemSusChemꢀ2015,ꢀ8,ꢀ603–608.ꢀ
60]ꢀ C.ꢀRocchiccioli-Deltcheff,ꢀR.ꢀThouvenot,ꢀJ.ꢀChem.ꢀRes.ꢀMꢀ1977,ꢀ0549–0571.ꢀ
61]ꢀ M.ꢀS.ꢀBalula,ꢀJ.ꢀA.ꢀGamelas,ꢀH.ꢀM.ꢀCarapuça,ꢀA.ꢀM.ꢀV.ꢀCavaleiro,ꢀW.ꢀSchlindwein,ꢀEur.ꢀJ.ꢀInorg.ꢀ
Chem.ꢀ2004,ꢀ2004,ꢀ619–628.ꢀ
[
[
[
62]ꢀ N.ꢀCasan-Pastor,ꢀL.ꢀC.ꢀW.ꢀBaker,ꢀinꢀPolyoxometalatesꢀPlatonicꢀSolidsꢀAnti-RetroviralꢀAct.,ꢀM.ꢀT.ꢀ
PopeꢀꢀandꢀA.ꢀMüllerꢀEds.ꢀ,ꢀ1994,ꢀpp.ꢀ203–217.ꢀ
[
[
63]ꢀ C.ꢀL.ꢀPitman,ꢀO.ꢀN.ꢀL.ꢀFinster,ꢀA.ꢀJ.ꢀM.ꢀMiller,ꢀChem.ꢀCommun.ꢀ2016,ꢀ52,ꢀ9105–9108.ꢀ
64]ꢀ N.ꢀ Elgrishi,ꢀ M.ꢀ B.ꢀ Chambers,ꢀ X.ꢀ Wang,ꢀ M.ꢀ Fontecave,ꢀ Chem.ꢀ Soc.ꢀ Rev.ꢀ 2017,ꢀ DOIꢀ
1
0.1039/C5CS00391A.ꢀ
[
[
[
65]ꢀ J.ꢀHawecker,ꢀJ.-M.ꢀLehn,ꢀR.ꢀZiessel,ꢀJ.ꢀChem.ꢀSoc.ꢀChem.ꢀCommun.ꢀ1984,ꢀ0,ꢀ328–330.ꢀ
66]ꢀ J.ꢀM.ꢀSmieja,ꢀC.ꢀP.ꢀKubiak,ꢀInorg.ꢀChem.ꢀ2010,ꢀ49,ꢀ9283–9289.ꢀ
67]ꢀ F.ꢀFranco,ꢀC.ꢀCometto,ꢀF.ꢀF.ꢀVallana,ꢀF.ꢀSordello,ꢀE.ꢀPriola,ꢀC.ꢀMinero,ꢀC.ꢀNervi,ꢀR.ꢀGobetto,ꢀChem.ꢀ
Commun.ꢀ2014,ꢀ50,ꢀ14670–14673.ꢀ
[
[
[
68]ꢀ J.ꢀAgarwal,ꢀT.ꢀW.ꢀShaw,ꢀH.ꢀF.ꢀSchaefer,ꢀA.ꢀB.ꢀBocarsly,ꢀInorg.ꢀChem.ꢀ2015,ꢀ54,ꢀ5285–5294.ꢀ
69]ꢀ S.ꢀSung,ꢀD.ꢀKumar,ꢀM.ꢀGil-Sepulcre,ꢀM.ꢀNippe,ꢀJ.ꢀAm.ꢀChem.ꢀSoc.ꢀ2017,ꢀ139,ꢀ13993–13996.ꢀ
70]ꢀ K.ꢀT.ꢀNgo,ꢀM.ꢀMcKinnon,ꢀB.ꢀMahanti,ꢀR.ꢀNarayanan,ꢀD.ꢀC.ꢀGrills,ꢀM.ꢀZ.ꢀErtem,ꢀJ.ꢀRochford,ꢀJ.ꢀAm.ꢀ
Chem.ꢀSoc.ꢀ2017,ꢀ139,ꢀ2604–2618.ꢀ
[
71]ꢀ E.ꢀE.ꢀBenson,ꢀK.ꢀA.ꢀGrice,ꢀJ.ꢀM.ꢀSmieja,ꢀC.ꢀP.ꢀKubiak,ꢀPolyhedronꢀ2013,ꢀ58,ꢀ229–234.ꢀ
ꢀ
15
This article is protected by copyright. All rights reserved.

European Journal of Inorganic Chemistry
10.1002/ejic.201800454
[
[
[
[
[
[
[
[
72]ꢀ F.ꢀ D.ꢀ Sypaseuth,ꢀ C.ꢀ Matlachowski,ꢀ M.ꢀ Weber,ꢀ M.ꢀ Schwalbe,ꢀ C.ꢀ C.ꢀ Tzschucke,ꢀ Chem.ꢀ –ꢀ Eur.ꢀ J.ꢀ
015,ꢀ21,ꢀ6564–6571.ꢀ
73]ꢀ H.ꢀY.ꢀV.ꢀChing,ꢀX.ꢀWang,ꢀM.ꢀHe,ꢀN.ꢀPerujoꢀHolland,ꢀR.ꢀGuillot,ꢀC.ꢀSlim,ꢀS.ꢀGriveau,ꢀH.ꢀC.ꢀBertrand,ꢀ
C.ꢀPolicar,ꢀF.ꢀBedioui,ꢀM.ꢀFontecave,ꢀInorg.ꢀChem.ꢀ2017,ꢀ56,ꢀ2966–2976.ꢀ
2
74]ꢀ N.ꢀP.ꢀLiyanage,ꢀH.ꢀA.ꢀDulaney,ꢀA.ꢀJ.ꢀHuckaba,ꢀJ.ꢀW.ꢀJurss,ꢀJ.ꢀH.ꢀDelcamp,ꢀInorg.ꢀChem.ꢀ2016,ꢀ55,ꢀ
6
085–6094.ꢀ
75]ꢀ J.ꢀK.ꢀNganga,ꢀC.ꢀR.ꢀSamanamu,ꢀJ.ꢀM.ꢀTanski,ꢀC.ꢀPacheco,ꢀC.ꢀSaucedo,ꢀV.ꢀS.ꢀBatista,ꢀK.ꢀA.ꢀGrice,ꢀM.ꢀ
Z.ꢀErtem,ꢀA.ꢀM.ꢀAngeles-Boza,ꢀInorg.ꢀChem.ꢀ2017,ꢀ56,ꢀ3214–3226.ꢀ
76]ꢀ S.ꢀJ.ꢀP.ꢀSpall,ꢀT.ꢀKeane,ꢀJ.ꢀTory,ꢀD.ꢀC.ꢀCocker,ꢀH.ꢀAdams,ꢀH.ꢀFowler,ꢀA.ꢀJ.ꢀH.ꢀM.ꢀMeijer,ꢀF.ꢀHartl,ꢀJ.ꢀA.ꢀ
Weinstein,ꢀInorg.ꢀChem.ꢀ2016,ꢀ55,ꢀ12568–12582.ꢀ
77]ꢀ M.ꢀ V.ꢀ Vollmer,ꢀ C.ꢀ W.ꢀ Machan,ꢀ M.ꢀ L.ꢀ Clark,ꢀ W.ꢀ E.ꢀ Antholine,ꢀ J.ꢀ Agarwal,ꢀ H.ꢀ F.ꢀ Schaefer,ꢀ C.ꢀ P.ꢀ
Kubiak,ꢀJ.ꢀR.ꢀWalensky,ꢀOrganometallicsꢀ2015,ꢀ34,ꢀ3–12.ꢀ
78]ꢀ C.ꢀRiplinger,ꢀM.ꢀD.ꢀSampson,ꢀA.ꢀM.ꢀRitzmann,ꢀC.ꢀP.ꢀKubiak,ꢀE.ꢀA.ꢀCarter,ꢀJ.ꢀAm.ꢀChem.ꢀSoc.ꢀ2014,ꢀ
1
36,ꢀ16285–16298.ꢀ
79]ꢀ C.ꢀWhite,ꢀA.ꢀYates,ꢀP.ꢀM.ꢀMaitlis,ꢀD.ꢀM.ꢀHeinekey,ꢀinꢀInorg.ꢀSynth.,ꢀJohnꢀWileyꢀ&ꢀSons,ꢀInc.,ꢀ2007,ꢀ
pp.ꢀ228–234.ꢀ
[
[
[
80]ꢀ U.ꢀKölle,ꢀM.ꢀGrätzel,ꢀAngew.ꢀChem.ꢀInt.ꢀEd.ꢀEngl.ꢀ1987,ꢀ26,ꢀ567–570.ꢀ
81]ꢀ E.ꢀRadkov,ꢀR.ꢀH.ꢀBeer,ꢀPolyhedronꢀ1995,ꢀ14,ꢀ2139–2143.ꢀ
82]ꢀ C.ꢀDablemont,ꢀFonctionnalisationꢀdeꢀPolyoxometallatesꢀàꢀStructureꢀdeꢀKeggin� :ꢀIntroductionꢀdeꢀ
LiaisonsꢀMétal-AzoteꢀMultiples,ꢀPhDꢀThesis,ꢀParisꢀ06,ꢀ2003.ꢀ
ꢀ
ꢀ
ꢀ
ꢀ
16
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European Journal of Inorganic Chemistry
10.1002/ejic.201800454
EntryꢀforꢀtheꢀTableꢀofꢀContentsꢀ
ꢀ
FULL PAPER
3
-
ꢀ
ꢀ
ꢀ
ꢀ
ꢀ
ꢀ
ꢀ
ꢀ
[
α-H
2
PW11
O
39{Rh(III)Cp*(OH
2
}]
Polyoxometalate electrocatalysis
was prepared by reaction between
[
a,b]
Marcello Girardi, Dominique
the monovacant Keggin-type [α-
[
a]
[b]
5
-
Platzer, Sophie Griveau, Fethi
H
2
PW11
O
39
]
and
] . It is closely
related to the CO reduction
electrocatalyst [Cp*Rh(III)(bpy)Cl]
[
b]
[a]
2
+
CO2
Bedioui, Anna Proust,* Sébastien
[
3 3
Cp*Rh(CH CN)
[
a]
+
-
Blanchard*
H , e
2
Rh OH2
+
Page No. – Page No.
by changing the bpy ligand by the
polyoxometalate, both acting as
Assessing the electrocatalytic
2+
redox
non-innocent
bidentate
properties of the {Cp*Rh(III)} -
HCOO-
ligands. The selectivity of the CO
2
Polyoxometalate derivative
H2
3-
reduction was altered from the
production of formate to dihydrogen.
ꢀ ꢀ [H
2
PW11
O
39{Rh(III)Cp*(OH
2
)}]
towards CO reduction
2
ꢀ
ꢀ
ꢀ
ꢀ
17
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